(The following section contains background material that, unless specifically stated otherwise, may or may not be prior art).
Advanced techniques for nanofabrication are in widespread use for research in biology, physics, chemistry and materials science. They are also essential manufacturing tools for electronics, photonics and many other existing and emerging areas of technology. Established nanolithographic methods (e.g., electron-beam lithography, deep ultraviolet photolithography, etc.) require elaborate and expensive systems that are capable only of patterning a narrow range of specialized materials over small areas on ultraflat surfaces of rigid inorganic substrates. These limitations and the importance of nanofabrication to progress in nanoscience and technology have created substantial interest in alternative techniques, such as those based on forms of contact printing, molding, embossing, and writing. See for example, C. A. Mirkin and J. A. Rogers, MRS Bull. 26, 530 (2001); B. Michel et al., IBM J. Res. & Dev. 45, 697 (2001); Y. Xia, J. A. Rogers, K. E. Paul, and G. M. Whitesides, Chem. Rev. 99, 1823 (1999). Although the basic operating principles of these techniques are conceptually old, recent research demonstrates that their resolution can be extended into the micron and nanometer regime by combining them with advanced materials and processing approaches. For example, elastomeric stamps and selfassembled monolayer inks (see L. H. Dubois and R. G. Nuzzo, Ann. Rev. Phys. Chem. 43, 437 (1992)) form the basis of a relatively new high-resolution printing technique. See A. Kumar and G. M. Whitesides, Appl. Phys. Lett. 63, 2002 (1993) and Y. Xia and G. M. Whitesides, Angew. Chem. Int. Ed. 37, 550 (1998). This method, known as microcontact printing (μCP), is rapidly becoming important for a range of applications in biotechnology, (J. Hyun, Y. J. Zhu, A. Liebmann-Vinson, T. P. Beebe, and A. Chilkoti, Langmuir 17, 6358 (2001)) plastic electronics, (J. A. Rogers, Z. Bao, K. W. Baldwin, A. Dodabalapur, B. Crone, V. R. Raju, V. Kuck, H. E. Katz, K. Amundson, J. Ewing, and P. Drzaic, Proc. Natl. Acad. Sci. USA, 98, 4835 (2001); J. A. Rogers, Science 291, 1502 (2001)) and fiber optics (J. A. Rogers, R. J. Jackan, G. M. Whitesides, J. L. Wagener, and A. M. Vengsarkar., Appl. Phys. Left. 70, 7 (1997)) where the relevant patterning requirements cannot be satisfied easily with conventional methods. Although the resolution of μCP is only ˜0.25 μm, this method and other emerging printing techniques, such as those that rely on imprinted polymer resists (“Imprint lithography with 25-nanometer resolution” Chou S Y, Krauss P R, Renstrom P J, SCIENCE 272 (5258): 85-87 Apr. 5, 1996)) and cold welded metals, have characteristics that make them potentially attractive for nanolithography: they offer fast, low-cost approaches for patterning flat or curved surfaces over large areas in a single processing step. While these methods appear to be useful for a range of applications, they are all generally subtractive in their operation: they either pattern sacrificial resists or they remove selected regions of an existing layer of material.